Piston ring



Jan. 3, 1956 H. E. SIETMAN 3- 5 PISTONRING Filed Feb. 9, 1952 12775 121 UT fiezzerli? PISTON RING Herbert E. Sietman, Bay Village, Ohio, assignor to Thompson Products,Inc., Cleveland, Ohio, a corporation of Ohio Application February 9, 1952, Serial No. 270,793

6 Claims. (Cl. 309-44) This invention relates to improvements in piston rings and has among other objects, to provide a simple and improved form of oil control ring made from a plurality of separate superimposed layers of split ring sections.

A further object of my invention is to provide an efficient form of oil control ring which may be inexpensively made from strip steel formed into separate split ring sections superimposed and interlocked to hold the gaps between adjacent ends of the ring sections in staggered relation with respect to each other.

A still further object of my invention is to provide a simple, cheap and efficient oil ring which may readily be made from strip steel and which is so arranged as to eliminate many of the forming stages and manufacturing difficulties heretofore encountered in them'anufacture of piston rings from continuous strip stock.

A still further object of my invention is to provide a simple and easily installed oil control piston ring wherein a plurality of scavenger elements are superimposed one on top the other with the slits therebetween in circumferentially spaced relation with respect toeach other within the piston, and are interlocked in this position by facing interlocking members connecting the scavenger elements together.

Another and more detailedobject of my invention is to improve upon and simplify the oil piston rings in present use by forming the ring from two separate flat split and slit annular ring sections, and interlocking the ring sections by loops formed integrally therewith and extending inwardly from the inner periphery thereof and bent toward the next adjacent ring section, to have interlocking engagement with each other.

These and other objects of my invention will appear from time to time as the following specification proceeds and with reference to the accompanying drawing wherein:

Figure l is an enlarged fragmentary plan view of an oil piston ring constructed in accordance with my invention;

Figure 2 is an enlarged detailed view showing the strip from which the ring is formed after the blanking operation and prior to forming in the form of an annular ring section;

Figure 3 is an enlarged end view of the ring taken from the inside thereof and looking toward the interlocking loops locking the ring sections from movement with respect to each other; and

Figure 4 is an enlarged fragmentary plan view of the ring shown in Figure 1.

In the embodiment of my invention illustrated in the drawing, the reference numeral indicates generally an oil control ring made from a plurality of separate superimposed split ring sections with the gaps of the adjacent ring sections maintained in non-registering relation with respect to each other by inwardly extending interlocking members or loops 1212 extending inwardly from the inner peripheries of the ring sections and alternately extending from the plane of one ring section along the inner wall of the next adjacent ring section, as will hereinafter more clearly appear as this specification proceeds.

Each split ring section may be made from flat strip steel stock of tool steel, such as S. A. E. 1095 containing 0.95% carbon which may be hardened after the blanking and forming operations and prior to the machining operation.

In Figure 2, a blank ring section is shown as having a series of equally spaced slits or cuts 15-45 forming the ring section into a plurality of scavenger elements 1616 connected together by the interlocking members or loops 1212, extending from adjacent scavenger elements at points spaced inwardly from the adjacent ends thereof, as shown. The slits 1515 may initially be rectilinear slits and the edges thereof may be inclined with respect to each other by a rolling or forming operation of the strip, thinning the outer edges thereof, or may be slit or punched to the form shown in Figure 2.

After the blanking operation, the strip ring section may then be formed into an annular form in any well known manner with the loops 12-12 extending inwardly therefrom toward the center of the ring. The loops 12-42 of each ring section may then be formed to the required form to extend to one side of the plane surface of the ring section and to provide interlocking members, adapted to have interlocking engagement with the oppositely extending loops of the next adjacent ring section, as will now be described.

The loops 12-12 may be coined to a reduced crosssection to impart sufiicient flexibility thereto to control the radial wall pressure of the ring. Coining may be effected by the punching dies forming the loops, thereby rendering the loops more or less flexible, depending upon the amount the section is reduced. This reduction in crosssection of the loops may be done prior to the operation of forming the ring in ring-like form and during the blanking and punching operations.

After coining the loops and reducing the cross-section thereof the required amount and forming the strip blank into an annular form, the loops of the rings may be punched to extend from the plane surface thereof and along the inner Wall of the next adjacent ring when the rings are assembled. The loops of the other ring may be punched in the same manner, and when the rings are assembled, may be inverted so the loops will extend in the spaces between the loops of the next adjacent ring. This lateral punching operation will draw the gaps between the scavenger elements together and will thus close the gaps between adjacent scavenger elements and draw the ring to substantially cylinder bore size for further forming and machining or grinding.

T he alternately arranged depending and upwardly projecting loops 12-1Z appear to be of concave and convex forms when looking down on the assembled ring, as in Figure 4, and thus interlock with each other and lock the ring sections from circumferential displacement with respect to each other, with the slits and gaps thereof out of registry with each other.

When inserting the rings in the piston and cylinder of an engine, two mating rings may be selected and placed in abutting and interlocking engagement with respect to each other and then inserted in the piston and cylinder of the engine in the usual manner. When in the piston and cylinder of the engine the radial wall pressure of the ring may be controlled by the flexibility of the coined loops 12-42 and the oil is scavenged from the cylinder wall for return to the crankcase by the slit ring segments or scavenging elements 16-46 conforming to the form of the cylinder and yieldably engaged therewith by the connecting loops 1212.

It may be seen from the foregoing that an improved oil control piston ring has been provided, consisting in two separable interlocking ring sections, which is of a simple, eflicient and durable construction and due to its simplicity and separability is cheaper to manufacture than bswi q s t as tqtq rci us l vma t mth h seen thatthering maybe formed irom fiat strip steel stock bya sirnplelpunching operationand a subseguent;forn1- ingoperation, forming the ring with a plurality of abutting alternately arrtt gcd circumferential scavenging vsurr fades y eldahly engag d lw thsth Walls f the yl d wit v connection-witheach other for interlocking the ring sections withthegapsot adjacent ring sections in non-registeringrelation.

2.]A piston ,ring comprising a plurality of flat split superimposedring sections having spacedfacing integrally formed'interlocking members extending inwardly of the inner peripheries thereof in spaced relation with respect toteach other, the interlocking members of adjacent' ring sections alternately extending up and down with respect to the plane surfaces of the associated ring, and havinginterengagement with each otherfor interlocking thelgaps ofgadjacent ring sections in non-registering relation.

' 3.IApiston ringcomprising a plurality of superimposed flat split annular iring sections radially slit throughout the circumference thereofand providing a plurality of scavengingelernents, the slit portions thereof terminating into Ema 381 .3@Xtcndinginterlockiug members connecting the sca en i el ent o c h and d p n g f o e ing section and extending upwardly from the next adjacent ring section :and i lt rlockingthe slits and gaps of adjacent ri 'gvsecti us out of registry with respect to eachother.

i4. Apiston ring eornprisingtwo superimposed flat split annulariring sections, each ring section being radially slit atregularly spaced intervals throughout the circumference thereof, dividing each ring segmentinto a plurality vof t1 'blm xlificrsswensi e e means t lockin the scavenging elements .of adjacent ring sections out 'loopsof a reduced cross sectional area adjacent their outer extremities, the loops of said-ring sections extending laterally from the plane surfaces thereof, and having interengaging connection with each other upon assembly of said ring sections, with the loops of adjacent ring sections facing each other and providing-radial cylinder wall pressure for said scavenging. elements.

5. In a piston ring, two separate split superimposed ring sections having a plurality'of alternately arranged circumierentially spaced radial slits therein dividingrthc ring sections into a plurality of scavenging elements, integrally formfidyfiq li l f ll g1119 1 1 936 c nnec sa sca eng ng elements together comprising loops extending inwardly from said scavenging elements frornpoints spaced circumferentially from the adjacent ends thereof, the loops of said ring sections extending from the plane surfaces thereof along it-he inner peripheralportions of thenext adiacc ri g ect n an h ing inte l c g en gement with each other and maintaining the slits and ,gaps of the ring :sections outof registry with each other, and also providing radialzwalltpressure.for theindividualscavengine-elements- "6. vApiston ring cornprisingtwo separate superimposed splitting sections having a plurality of circumferentially spaced radial slits therein dividing the ring sections into a plurality of cylinder wall scavenging elements, means connecting said scavenging elements together including'a plurality .of inwardly extendingintegrally formed loops extending inwardly frorn said scavenging elements from points spaccdfrotn the adjacent ends thereof, said loops being. of reduced,crossrsectional areaiin the region thereof extending across .,the slit portions of said ring sections, and said loops-extending fromtthe plane of one ring heyondthesahutting planerofthevnext adjacent ringand hav-r ing inter ngagen e'nt .twithfifich other and interlockingthe skips newer ai men -e ds sa d in s n out o r gist y tw sah-q hsr and s e g yl nde wal pressure agai nst the'scavenging velements when in thepiston and cylinder of an engine;

Refe sncesoit d intll fil of thi p t n UNITED .STJIATES E TENT 2,482990 tolson Sept. 27, 194-9 2,6Q2fl15 Shirk July s, 1952 .FognroN PATENTS 643,4'88 .Greatfliritain Sept. 20, 19.50 

